Communication systems operate to effectuate the communication of data. Advancements in communication technologies have permitted the implementation of communication systems capable of communicating data at increased data communication rates and also in manners to facilitate recovery of the informational content thereof subsequent to its communication upon a non-ideal communication channel.
Radio communication systems are emblematic of communication systems that have incorporated advancements in communication technologies and are permitting of use to effectuate high data rate communication services. Radio communication systems differ from their wireline counterparts in that communication channels upon which data is communicated are defined upon radio links formed of portions of the electromagnetic spectrum. Wireline connections interconnecting communication stations are obviated.
Many varied types of radio communication systems have been developed and implemented for general, and other, communication services. Cellular communication systems are examplementary of radio communication systems that have been implemented and that have achieved significant levels of consumer penetration, i.e., usage.
Cellular communication systems, historically, have been used primarily to effectuate circuit-switched voice communications as well as, on occasion, to effectuate low-band width data communication services.
The technological advancements in communication technologies have been applied to cellular communication systems to permit a technical, migration path of cellular technology through successive generations of communication system technologies. First-generation systems generally refer to cellular communication systems that utilize analog communication techniques. Second-generation (2G) cellular communication systems refer, generally, to systems that utilize digital communication techniques. So-called 2.5 G communication systems refer, generally, to digital cellular communication systems that provide for variable bit rate communications and for the creation of alternate paths upon which to communicate packet-switched data in core networks defined in such systems. And, third-generation (3G) communication systems refer, generally, to systems that further support larger band-width communication service applications and support quality of service (QoS) provisioning.
Various different, and sometimes competing, 3G systems are undergoing development for future implementation. And, global harmonization efforts are ongoing. The third generation partnership project (3GPP) is standardizing various of the 3 G communication systems, such as the WCDMA (Wideband Code-Division Multiple Access) system, the EDGE (Enhanced Data for GSM Evolution) system, and the TD-SCDMA (Time-Division Space-Code-Division Multiple Access) system. And, a GSM/GPRS (General System for Mobile Communications/General Packet Radio Service), a 2.5G system, is presently undergoing implementation.
Cellular communication systems are generally public-access systems in that members of the general public are permitted to communicate therethrough pursuant to a service subscription to the communication system.
Other radio communication systems have analogously also benefited from, or have been made possible, as a result of advancements in communication technologies. For instance, WLANs (Wireless Local Area Networks) have been made possible as a result of advancements in communication technologies. While initially implemented generally as private systems, increasingly, public wireless communications are extending into WLAN environments. WLANs permit high data rate communication services to be effectuated therethrough. And, effectuation of such high data rate communication services are generally more desirably implemented by way of a WLAN, when available, than through a cellular communication system. WLANs are constructed, for instance, to be operable pursuant to an IEEE 802.11 operating specification.
A mobile node can be constructed to permit its operation, i.e., communication, in the WLAN or a cellular communication system, such as the GPRS (General Packet Radio Service) network. The separate systems are, as noted, operable pursuant to separate technologies. Dual-mode operational capability is required of such a mobile node. Data communication services, such as communication services that communicate IP (Internet Protocol)—formatted data are able to be effectuated by either of the GPRS network and the WLAN.
Proposals have been set forth to permit roaming of a mobile node between technologies, i.e., between the UMTS system and the WLAN. However, existing proposals do not adequately provide support for dormant mode operation of a mobile node when the mobile node roams between the inter-technology, i.e., the UMTS and the WLAN.
Accordingly, a manner by which to provide support for dormant mode operation when a mobile node roams between inter-technologies, such as between a UMTS and a WLAN, would be advantageous.
It is in light of this background information related to high data rate communication services that the significant improvements of the present invention have evolved.